This application is a 371 of PCT EP00/06296 filed Jul. 5, 2000.
The present invention relates to zwitterionic polyamines and a process for their production by alkoxylation of polyamines and introduction of anionic groups.
EP-A-0,111,976 relates to watersoluble zwitterionic compounds having clay soil removal/anti-redeposition properties. An example of such a compound is a with chlorosulfonic acid sulfated quaternized addition product of ethoxylated tetraethylenepentamine with a total degree of ethoxylation of 21.
EP-A-0,112,592 relates to zwitterionic polymers which are for example obtained by alkoxylation of polyalkyleneamines such as triethylenetetramine or tetraethylenepentamine or of polyethyleneimines, sulfonation of the alkoxylated products and subsequent quaternization. The zwitterionic products disclosed in the above patents have clay-soil removal and anti-redeposition properties when used in detergent compositions, however their effectiveness in dispersing and removing clay embedded in the fabric into the laundry liquor is not sufficient. Furthermore the specifically disclosed compounds of this literature reference are thermally instable.
GB-A-2,220,215 relates to sulfated alkoxylated mono- or polyamines derived from polymethlenediamines with 2-6 methylene groups between the nitrogen atoms or polyalkylenepolyamines in which the alkylene contains 2-4 carbon atoms and containing 3-6 amino groups. They may bear a long chain-alkyl substituent at one of the nitrogen atoms and are quaternized. However it was found that these polymers are not favorable for clay soil removal within laundry operations where anionic surfactants are present.
U.S. Pat. No. 4,739,094 discloses alkoxylated aminopolyethers containing units of ethylene oxide and propylene oxide and having a molecular weight of from 10,000 to 150,000. The alkoxylated aminopolyethers are water-soluble and are used in 5 to 60% strength by weight aqueous solution in the preparation of coal/water slurries. If appropriate, the alkoxylated aminopolyethers can also be reacted with carboxylic acid anhydrides, amidosulfonic acids and urea, acid chlorides of sulfur or of phosphorus or chloroacetic acid esters. The reaction products can be converted into ionic compounds by subsequent neutralization or hydrolysis.
It is therefore an object of the invention to provide new polymers with improved thermal stability.
The above object is achieved with a zwitterionic polyamine comprising a linear or branched hydrophobic polyamine backbone having 2 to 10 tertiary amino nitrogen atoms and a spacer between two tertiary amino nitrogen atoms wherein the spacer is selected from the group consisting of C3-C15-alkylene, C5-C15-cycloalkylene 
wherein in formula I, II and III
B is C2-C16-alkylene, C5-C15-cycloalkylene
D is C4-C16-alkylene, C5-C15-cycloalkylene
O is 1 or 2,
p is 3 to 8
wherein in formula IV
R=C1- to C22-alkyl or C7-C22-aralkyl and n=3 to 6,
at least one tertiary amine end group of the polyamine backbone contains two groups having the formula 
wherein
A means an ethylene oxide unit, a propylene oxide unit, a unit of butylene oxides and a tetrahydrofuran unit,
n is a number of from 1 to 50,
X is xe2x80x94SO3M, xe2x80x94CH2xe2x80x94CH2xe2x80x94SO3M, xe2x80x94CH2xe2x80x94CH2xe2x80x94CH2xe2x80x94SO3M, 
xe2x80x83with the proviso that in formula VI one X may also be hydrogen and
M is hydrogen, alkali metal or ammonium,
or contains one group of formula V or VI and one group selected from radicals consisting of 
C1- to C22-alkyl and C7-C22-aralkyl, the meaning of A and n is the same as in formula V or VI,
said zwitterionic polyamine having a molecular weight up to 9,000 optionally containing up to 100% of the nitrogen atoms quaternized.
The object is also achieved with a process for the production of a zwitterionic polyamine which comprises a first step wherein
(i) a linear or branched hydrophobic polyamine having 2to 10 tertiary amino nitrogen atoms and a spacer between two tertiary amino nitrogen atoms wherein the spacer is selected from the group consisting of
C8- to C16-alkylene, C5- to C15-cycloalkylene 
wherein in formula I, II and III
B is C2-C16-alkylene, C5-C15-cycloalkylene
D is C4-C16-alkylene, C5-C15-cycloalkylene
o is 1 or 2,
p is 3 to 8
wherein in formula IV
R=C1- to C22-alkyl or C7-C22-aralkyl and n=2 to 6,
is reacted with
(ii) at least one C2- to C4-alkylene oxide or tetrahydro furane at such a ratio that on each NH group of the polyamine 1 to 50 units of the alkylene oxide or of tetrahydrofurane are added,
a second step wherein the alkoxylated polyamine obtained in the first step is reacted with a compound selected from the group consisting of a halogen sulfonic acid, halogen phosphorous acid, vinyl sulfonic acid, propane sultone, halogen acetic acid, acrylic acid, methacrylic acid, vinyl phosphorous acid and the alkali metal or ammonium salts of the said acids, in such a manner that at least one tertiary amine end group of the alkoxylated polyamine contains two groups having the formula 
wherein
A means an ethylene oxide unit, a propylene oxide unit, a unit of butylene oxides and a tetrahydrofuran unit,
n is a number of from 1 to 50,
X is xe2x80x94SO3M, xe2x80x94CH2xe2x80x94CH2xe2x80x94SO3M, xe2x80x94CH2xe2x80x94CH2xe2x80x94CH2xe2x80x94SO3M, 
xe2x80x83with the proviso that in formula VI one X may also be hydrogen and
M is hydrogen, alkali metal or ammonium,
or contains one group of formula V or VI and one group selected from radicals consisting of 
the meaning of A and n is the same as in formula V or VI,
and optionally
a third step wherein up to 100% of the tertiary nitrogen atoms of the reaction product obtained in the second step are quaternized, said degree of quaternization, may also be obtained by first quaternizing the reaction product obtained in the first step and subsequently carrying out the second step.
Preferred zwitterionic polyamines contain two groups of formula V or VI attached to the tertiary nitrogen atoms of the end groups of the polyamines. Especially preferred zwitterionic polyamines contain the nitrogen atoms of the end groups of the polyamine backbone quaternized and, as substituents, two groups of formula V or VI and one C1- to C22-alkyl group or a hydroxyalkyl group. In most cases the nitrogen end groups of the polyamine backbone are quaternized and contain as substituents two groups of formula V and a C1- to C22-alkyl group. Other preferred zwitterionic polyamines contain quaternized amino nitrogen end groups bearing, as substituents, two groups of formula V and a hydroxyethyl or hydroxypropyl group.
The substituent A in formulae V and VI may have the following structures: 
Other zwitterionic polyamines are charaterized in that the spacer between two nitrogen atoms of the polyamine backbone is a cyclic C5- to C15-alkylene group.
Of particular interest are zwitterionic polyamines wherein the polyamine backbone between the nitrogen atoms is derived from an amine selected from the group consisting of bis(hexamethylene)triamine, N,Nxe2x80x2-bis(3-aminopropyl)piperazine, N,Nxe2x80x2-bis(2-aminoethyl)piperazine and bis(3-aminopropyl)hexamethylenediamine and wherein at least one tertiary amine end group of the polyamine backbone contains two groups having formula V or VI.
The zwitterionic polyamine is derived from a linear or branched hydrophobic polyamine. The backbone of the polyamine contains 2 to 10 tertiary amino nitrogen atoms and has one spacer between two tertiary amino nitrogen atoms. Polyamines containing a C8- to C16-alkylene group as spacer are for example 1,8-diaminooctane, 1,10-diaminodecane and 1,12-diaminododecane. Examples of suitable polyamines containing the above spacers of formula I-IV are dipropylenetriamine, tripropylenetetramine, bis(hexamethylene)triamine, bis(octamethylene)triamine, aminoethylpropylenediamine, aminoethylbutylenediamine, aminoethylhexamethylenediamine, N,Nxe2x80x2-bis(aminoethyl)propylenediamine, N,Nxe2x80x2-bis(aminoethyl)butylenediamine, N,Nxe2x80x2-bis(aminoethyl)hexamethylenediamine, N,Nxe2x80x2-bis(aminopropyl)ethylendiamine, N,Nxe2x80x2-bis(aminopropyl)butylenediamine, N,Nxe2x80x2-bis(aminopropyl)butylendiamine, N,Nxe2x80x2-bis(aminopropyl)hexamethylenediamine, N,Nxe2x80x2-bis(aminopropyl)ethylenediamine, N,Nxe2x80x2-bis(3-aminopropyl)-N-methylamine, N-(dimethylaminopropyl)propylenediamine, N,Nxe2x80x2-dimethyl-1,3-diaminopropane; N,N-bis (3-aminopropyl) -N-octylamine and N,N-bis (3-aminopropyl)-N-ethylamine.
Polyamines with spacers consisting of a cyclic C5- to C15-alkylene group are for example 1,3-cyclohexylenediamine, 4-methyl-1,3-cyclohexylenediamine, 2-methyl-1,3-cyclohexylenediamine, isophoronediamine and 4,4xe2x80x2-diamino(biscyclohexylene)methane.
The zwitterionic polyamines can also be prepared from polyamines which contain other cyclic spacers. Such polyamines are, for example, o-, m-, and p-di(aminomethylen)benzene, N,Nxe2x80x2-bis(aminoethyl)piperazine, N,Nxe2x80x2-bis(aminopropylpiperazine and N-aminopropylpiperazine.
Especially preferred zwitterionic polyamines may be characterized by the following formula 
wherein
EO is xe2x80x94CH2xe2x80x94CH2xe2x80x94Oxe2x80x94
M is H, Na, K or ammonium and
n is 15-25.
The weight average molecular weight Mw of the zwitterionic polypolyamines is up to 9,000, preferably of from 1,500 to 7,500 and more preferably of from 2000 to 6,000. The zwitterionic polyamines can be soluble or dispersible in water and aqueous or non-aqueous solvents or formulations. In one preferred embodiment of the present invention they are water-soluble. These water soluble zwitterionic polyetherpolyamines are used in laundry detergent compositions and have an excellent degree of clay soil removal from fabrics.
The zwitterionic polyamines are net anionic. Preferably the average number of anionic charges resulting from groups X in formulae V and VI exceeds the average number of cationic charges resulting from protonated or quaternized amine groups by a factor of more than 1.2, more preferred of more than 1.5, most preferred of more than 1.8.
The zwitterionic polyamines of the invention are prepared in a multistage process. In the first step of this process a linear or branched polyamine having 2 to 10 primary or secondary nitrogen atoms and containing one of the above spacers between two nitrogen atoms is reacted with a least one C2- to C4-alkylene oxide or tetrahydrofurane at such a ratio that on each NH group of the polyamine 1 to 50, preferably 15 to 25 alkylene oxide units or tetrahydrofurane units are added. Ethylene oxide and propylene oxide are the preferred alkoxylating agents. If a mixture of alkylene oxides is added to the amino nitrogen then the polymerized alkylene oxides may be present in statistical distribution or as blocks. For example one can add first 10 to 20 of ethylene oxide units per NH group in the polyamine and then add 5 to 10 propylene oxide units or vice versa.
Most preferred ethylene oxide alone or combinations of 1-15% propylene oxide or 1-10% butylene oxide with 85-99, 90-99% ethylene oxide respectively are used. If a combination of ethylene oxide and propylene oxide or butylene oxide is used preferably the propylene oxide or butylene oxide is reacted first with the NH groups of the polyamine and the ethylene oxide is added after that.
The above described procedure gives polyalkoxylated products which have groups of formula
xe2x80x94(A)nxe2x80x94H,
wherein A and n have the meaning given for formula V.
The linear or branched polyamines are preferably ethoxylated in the first step of the production of the zwitterionic polyamines.
In order to produce zwitterionic polyamines having end groups of formula VI a linear or branched polyamine having 2 to 10 nitrogen atoms and containing at least 2 primary or secondary amino nitrogen groups is reacted with up to 1 glycidol per NH group. The reaction product thus obtained is in the first step of the process according to the invention alkoxylated at the OH groups and remaining NH groups as described above. The reaction of glycidol with said polyamine may be carried out to such an extent that at least 50 to 100% of the NH groups of the polyamine are substituted by one glycidol unit.
In the second step of the production of the zwitterionic polyamines an anionic group is introduced into the alkoxylated polyamines obtained in the first step. This may be achieved by reacting the alkoxylated polyamines in a Michael type addition reaction with acrylic acid, methacrylic acid, vinyl sulfonic acid, vinylphosphonic acid or their alkalimetal or ammonium salts or by reacting them with halogen sulfonic acid, halogen phosphorous acid, propane sultone or halogen acetic acid. The preferred component for introducing anionic groups is chlorosulfonic acid.
Dependent on the amount of anionic agent used in the second step zwitterionic products are obtained which contain either two substituents of formula V or VI or contain only one of them, if, for instance, only one mole of the anionic agent is used per one mole of OH end group of the alkoxylated polyamine. The non-reacted end groups of the alkoxylated polyamine may be characterized by a group selected from radicals consisting of 
the meaning of A and n is the same as in formula V or VI.
The degree of substitution of the OH groups in the alkoxylated polyamines is such, that the finally resulting zwitterionic polyamine is net anionic at the pH of intended use; e.g. from 40% up to 100% of the OH group a substituted by an anionic group. Preferably more than 60%, more preferred more then 80%, most preferred 90-100% of the OH-groups are substituted by an anionic group.
Moreover the zwitterionic polyamines may also contain only one substituent of formula V or VI and instead of the above described radicals a C1-C22-alkyl group or a C7- to C22-aralkyl group. Such compounds result when the polyamine used in the first step contains secondary amino groups having a C1- to C22-alkyl or a C7- to C22-aralkyl substituent.
The zwitterionic polyamines obtained in the second step may optionally reacted in a third step with a quaternizing agent. Alternatively, quaternized products may also be obtained by first quaternizing the reaction products obtained in the first step, i.e. the polyalkoxylated polyamines. Suitable quaternization agents are for example C1- to C22-alkylhalides, C7- to C22-aralkyl halides C1-C2-dialkylsulfates or alkylene oxides. Examples of quaternizing agents are dimethyl sulfate, diethyl sulfate, methyl chloride, ethyl chloride, methyl bromide, ethyl bromide, butyl bromide, hexyl chloride, benzyl chloride, benzyl bromide, ethylene oxide or propylene oxide. Dialkylsulfates, C1-C4-alkylchlorides and benzyl chloride are preferred. Dimethyl sulfate is the most preferred quaternizing agent. Up to 100% of the tertiary nitrogen atoms of the zwitterionic polyamine may be quaternized. If there is a quaternization step, then the degree of quaternization is, for example, 10 to 100%, preferably at least 25% and more preferably 75 to 100%.
According to a preferred embodiment of the process for the production of zwitterionic polyamines in the first step
(i) a polyamine selected from the group consisting of bis(hexamethylene)triamine, bis(aminopropyl)piperazine, N,Nxe2x80x2-bis(aminopropyl)hexamethylenediamine and N,N,Nxe2x80x2,Nxe2x80x3,Nxe2x80x3-penta(2,3-dihydroxypropyl)-bis(hexamethylene)triaminexe2x80x94the latter is obtained by reacting bis(hexamethylene)triamine with glycidol in a molar ratio of 1:5)xe2x80x94is reacted with
(ii) an alkylene oxide selected from the group consisting of ethylene oxide, propylene oxide, butylene oxide and mixtures of the said alkylene oxides, at such a ratio that on each NH group of the polyamine 15 to 40 units of the alkylene oxide are added,
in the second step
the alkoxylated polyamine obtained in the first step is reacted with chlorosulfonic acid in such ratio that at least one teritary end group of the polyamine contains two groups having the formula
xe2x80x94(A)nxe2x80x94Xxe2x80x83xe2x80x83(V),
wherein
A is an ethylene oxide unit, a propylene oxide unit or a butylene oxide unit,
n is 15-40 and
X is SO3H,
and
in the third step
the zwitterionic reaction product of the second step is quaternized with dimethyl sulfate, methyl chloride or benzyl chloride.
The quaternization can also be carried out as a second step in the multistage process for the production of zwitterionic polyamines. The alkoxylated polyamine obtained in the first step is quaternized up to 100% and subsequently reacted with chlorosulfonic acid or another agent capable to introduce an anionic group. This procedure is preferred for the production of quaternized zwitterionic polyamines.
The zwitterionic polyamines are used as additive in laundry detergent compositions which provide enhanced hydrophilic soil, inter alia, clay, removal benefits. The new zwitterionic polyamines are especially useful in detergents comprising a surfactant system which comprises mid-chain branched surfactants inter alia mid-chain branched alkyl sulphonates. The zwitterionic polyamines are additionally used as effective dispersants for hydrophilic particles within aqueous and nonaqueous solutions and formulations.
The degree of quaternization and of sulfatation was determined by 1H-NMR. The amine number was determined by amine titration according to DIN 16 945.